please tell me where I went wrong.
A proton is moving parallel to a uniform electric field. The electric field accelerates the proton and increases its linear momentum to 5.0x 10^-23 kg m/s from 1.4x 10^-23 kg m/s in a time of 6.5x 10^-6 s. What is the magnitude of the electric field?
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Physics - bobpursley, Thursday, August 30, 2007 at 9:34am
Impulse = change in momentum
coulomb force*time=changemomentum
Eq*time= changemomentum
solve for E
My working out is as follows but it is incorrect:
Eq*time=changemomentum
Eq= (3.6x10^-23kg*m/s)(6.5x10^-6s)
Eq= 5.538451538x 10^-18
Please help
You should have written
Eq*time=changemomentum
E*q*(6.5x10^-6s)= 3.6x10^-23kg*m/s
solve for E.
q = 1.6*10^-19 Coulombs
If you do the numbers correctly, the units of E will be Newtons (or kg m/s^2) per Coulomb
To find the magnitude of the electric field, you need to use the equation provided: Eq * time = changemomentum.
You correctly applied the equation, but there's a small mistake in your calculation.
Eq = (3.6x10^-23 kg*m/s) * (6.5x10^-6 s)
Eq = 2.34x10^-28 N⋅s
So the magnitude of the electric field is 2.34x10^-28 N⋅s.